Sometimes I just like to sit outside during this time of year and have a beer next to a firepit. It's warm enough, but I would be even more comfortable with a folding chair that has a heated seat.
According to Hammacher Schlemmer, the seat has "undetectable" carbon fibre heating elements that can reach temperatures between 120 and 140 degrees for up to 2.5 hours on the highest setting. The battery can be charged in about the same amount of time via an AC outlet or the included automobile adaptor. It also has some nice extras like a tray with a cupholder, pockets for stashing snacks and a sturdy fabric that won't sag when you sit. Although, that last bit would be put to the test if you were pushing its 270 pound weight limit. Available for $US120. [Hammacher via Crunchgear]